1.3.1 Multiple Dates/Times: The five original NGA stations (Australia, Bahrain,
England, Argentina, Ecuador) have archived data available for one day of each week for
1990 and 1991. Archived GPS data is available for every day of the week for all stations
from 1992 on. GPS data is available for Washington, D.C. from May 1995 on. GPS data is
available for Beijing, China from October 1995 on.

6.5 Custom Order Process: Customers must contact the Identification Information
Section Point of Contact. If available, please provide an Internet address to which the
data files can be sent. This address should be accessible via File Transfer Protocol
(FTP). The GPS data files can also be sent hard copy on 3.5 inch diskettes.

6.6 Technical Prerequisites: The NGA GPS data files are binary files in Ashtech
format. They include ranging, phase, and ephemeris data. These files can easily be
converted to RINEX format (a universal receiver independent format). Thirty second GPS
data for one station for one day is approximately 2-2.5 megabytes uncompressed (1-1.5
megabytes compressed).